This invention relates in general to a circuit arrangement for generating a binary-coded pulse train, and more particularly to a circuit arrangement for generating a pulse train having a predetermined first pulse spacing (a) and a second pulse spacing (b) differing from the first by an integral factor greater than one, which pulse spacings are assigned to the binary ZERO and the binary ONE, respectively, dependent upon a predetermined n-bit binary word.
Binary-coded pulse trains are needed, for example, to transmit information by pulse-code modulation, where the binary-coded information lies in the different pulse spacings of the pulse train. A method known from German Published Patent Application (DT-OS) No. 2,503,083 assigns the binary ZERO to a first pulse spacing, and the binary ONE to a pulse spacing which is twice as large. Such a limitation is not necessary, however, in particular, the second pulse spacing may be an integral multiple of, i.e., m times, the first pulse spacing.
The method disclosed in the above German published patent application is used for infrared remote control of television sets. This specific use is not imperative, either. For example, phono equipment and radio sets can be remotely controlled in this manner, too. Even the specified assignment of the two binary state to the two pulse spacings can be reversed, as is described, for example, in applicant's prior German application No. P 27 37 467.0-32.
In the arrangement disclosed in that prior application, which also relates to a remote control arrangement using pulse-code modulation, each remote control command consists of an n-bit binary word which is generated by pressing the key of a keyboard and determines the position and spacing of the pulses of the transmitted pulse train.